Vehicle Routing Problem with Time Window (VRPTW) can be considered as one of the most critical problems in today logistics industry.

VRPTW seeks to minimize the total transportation cost, improve the efficiency of delivery system and hence raise the customers’ satisfactory. In the paper, the model was developed to find the sets of routes that attains minimum shipping cost in compulsory time window. The system of single depot and multiple customers operated by a set of vehicles was investigated.

The study had two approaches to the problem. The first approach aimed to find the optimal set of VRPTW problem by using simplex method and CPLEX solver. The mixed integer mathematical model was proposed based on the realistic scenario of the company. The second approach, meta-heuristic method of Genetic Algorithm was implemented to find out the best-so-far route in terms of defined constraints by using Python.

The paper also studied about order allocation problem, which objective was to determine the volume of goods flow in and flow out at VTA’s warehouses. Keywords: Vehicle Routing Problem with Time Window, Order Allocation, Exact Methods, Genetic Algorithms, Last-mile Delivery.